From Historical Rutland: an illustrated history of Rutland, Vermont, from the granting of the charter in 1761 to 1911 by Rev. F. E. Davison, Rutland, Vt.: P.H. Brehmer, 1911, page 16:
In March, 1778, Rutland, was made the headquarters for the State Troops. That same year a fort was erected at Center Rutland, on the hill east of the falls, known as Gookins' falls, and named Fort Ranger. It covered two or more acres, was made of unhewn hemlock logs or pickets, sunk in a trench five feet deep, and rising fifteen feet high, sharpened at the top and inclining outward and accommodating two or three hundred troops. In the northwest section a block house was built, forty feet square and two stories high and supplied on all sides with port holes. This fort was used as headquarters, and a depot of supplies for other forts, until 1781, when the headquarters were removed to Castleton.
During the War of the Rebellion, the present fair ground was used as a veteran reserve camp, and called Camp Fairbanks, in honor of Governor Fairbanks. The first and Second Regiments, mustered into service at Rutland, were camped here for several weeks.